ROTATIONAL INVARIANCE IN THE M(ATRIX) FORMULATION OF TYPE IIB THEORY

The matrix model formulation of M-theory can be generalized by compact ification to ten-dimensional type Il string theory, formulated in the infinite momentum frame. Both the type IIA and IIB string theories can be formulated in this way. In the M-theory and type IIA cases, the tr ansverse rotational invariance is manifest, but in the IIB case, one o f the transverse dimensions materializes in a completely different way from the other seven. The full O(8) rotational symmetry then follows in a surprising way from the electric-magnetic duality of supersymmetr ic Yang-Mills field theory. (C) 1997 Elsevier Science B.V.